SEGMENT-EDITOR : Segment-Ranges

Not all motion-laws have a Segment-Range.

Segment-Range parameters edit the start and end of the mathematical-function that defines the motion-law.


Segment-Range does NOT change the Segment-Width.

Segment-Range does not change the X-axis values of the Segment-Start or Segment-End, and thus the Segment-Width does not change.


Start and End Segment Ranges

Start and End Segment Ranges

 Segment Ranges  - available with a selection of Traditional Motion-Laws.

The parameters are:

Start-Range [Default = 0]
End-Range [Default = 1]

0 ≤ Start Range < End Range ≤ 1

Notes:

Position at the start and end of the segment do not NOT change.

SegmentRange-0-0

The images shows the acceleration graph of a Modified Sinusoid motion-law.

Image 1

Default Segment-Range parameter values.

Start-Range = 0.0
End-Range = 1.0

Segment-Width does not change.

SegmentRange-0210

Image 2

Start-Range = 0.2
End-Range = 1.0

A Start-Range = 0.2 removes 20% at the start of the Modified-Sinusoid segment mathematically function

SegmentRange-1008

Image 3

Start-Range = 0.0
End-Range = 0.8

The End-Range = 0.8 removes 20% at the end of the Modified-Sinusoid segment.

The Segment-Width does not change.

see also: Segment Editor: Segment-Width, Segment Editor: Parameters

Dwell-Rise-Dwell Asymmetrical Motion

Symmetrical Motions

The crossover  [or vice-versa] is usually at the mid-point of the Segment-Width.

Asymmetrical Motions

The crossover is not at the mid-point of the Segment Width.

When to use Asymmetrical Motions

You want the mechanism tool to accelerate quickly from a dwell until it reaches a peak velocity that is sooner than the mid-point of the motion-law, It is then followed with a deceleration that is longer than the standard deceleration duration.

Or vice-versa.

AsymmetricalModSine

You can model an asymmetrical motion with two segments that have the same motion law - for example a Modified Sinusoid.

Orange Line graph :

Symmetrical Mod-Sine Motion-Law : λ = 0.5

This motion-law is usually specified with one standard Mod-Sine segment.

However, here, it has two Mod-Sine segments.

Segment 1

Machine angle: 0 - 180º  [ 0 - 0.5 of total duration]

Displacement : 0 - 50 units

Segment Ranges = 0 and 0.5.

Segment 2

Machine angle: 180 - 360º [ 0.5 - 1.0 of total duration]

Displacement : 50- 100 units

Segment Ranges = 0.5 and 1.


Black Line graph

Asymmetrical Mod-Sine Motion-Law : λ = 0.25

Crossover @ 0.25 = 90º machine angle.

It also two Mod-Sine segments:

Segment 1:

Machine angle: 0 - 90º [0 - 0.25 of total duration]

Displacement : 0 - 25 units

Segment Ranges : 0 and 0.5.

Segment 2:

Machine angle: 90 - 360º [0.75 - 1.0 of total duration]

Displacement : 75 - 100 units

Segment Ranges = 0.5 and 1.

Characteristics Values of Asymmetrical Motion-Law.

Velocity : No Change to Symmetrical Motion-Law.

Acceleration: Segment 1 :  Cas = Ca / 2λ ;

Acceleration: Segment 2 :  Cas = Ca / 2(1-λ)

Tutorial and Reference Help Files for MechDesigner and MotionDesigner 13.2 + © Machine, Mechanism, Motion and Cam Design Software by PSMotion Ltd